翻訳と辞書
Words near each other
・ Anamori-inari Station
・ Anamorph (disambiguation)
・ Anamorph (film)
・ Anamorphic format
・ Anamorphic stretch transform
・ Anamorphic widescreen
・ Anamorphism
・ Anamorphosis
・ Anamorphosis (biology)
・ Anamorphosis (EP)
・ Anamorphosée
・ Anamorós
・ Anamosa Limestone
・ Anamosa School District
・ Anamosa State Penitentiary
Analytical hierarchy
・ Analytical jurisprudence
・ Analytical light scattering
・ Analytical Marxism
・ Analytical mechanics
・ Analytical Methods (journal)
・ Analytical nebulizer
・ Analytical Performance Modeling
・ Analytical phonics
・ Analytical procedures (finance auditing)
・ Analytical profile index
・ Analytical psychology
・ Analytical quality control
・ Analytical regularization
・ Analytical Review


Dictionary Lists
翻訳と辞書 辞書検索 [ 開発暫定版 ]
スポンサード リンク

Analytical hierarchy : ウィキペディア英語版
Analytical hierarchy

In mathematical logic and descriptive set theory, the analytical hierarchy is an extension of the arithmetical hierarchy. The analytical hierarchy of formulas includes formulas in the language of second-order arithmetic, which can have quantifiers over both the set of natural numbers, \mathbb, and over functions from \mathbb to \mathbb. The analytical hierarchy of sets classifies sets by the formulas that can be used to define them; it is the lightface version of the projective hierarchy.
== The analytical hierarchy of formulas ==
The notation \Sigma^1_0 = \Pi^1_0 = \Delta^1_0
indicates the class of formulas in the language of second-order arithmetic with no set quantifiers. This language does not contain set parameters. The Greek letters here are lightface symbols, which indicate this choice of language. Each corresponding boldface symbol denotes the corresponding class of formulas in the extended language with a parameter for each real; see projective hierarchy for details.
A formula in the language of second-order arithmetic is defined to be \Sigma^1_ if it is logically equivalent to a formula of the form \exists X_1\cdots \exists X_k \psi where \psi is \Pi^1_. A formula is defined to be \Pi^1_ if it is logically equivalent to a formula of the form \forall X_1\cdots \forall X_k \psi where \psi is \Sigma^1_. This inductive definition defines the classes \Sigma^1_n and \Pi^1_n for every natural number n.
Because every formula has a prenex normal form, every formula in the language of second-order arithmetic is \Sigma^1_n or \Pi^1_n for some n. Because meaningless quantifiers can be added to any formula, once a formula is given the classification \Sigma^1_n or \Pi^1_n for some n it will be given the classifications \Sigma^1_m and \Pi^1_m for all m greater than n.

抄文引用元・出典: フリー百科事典『 ウィキペディア(Wikipedia)
ウィキペディアで「Analytical hierarchy」の詳細全文を読む



スポンサード リンク
翻訳と辞書 : 翻訳のためのインターネットリソース

Copyright(C) kotoba.ne.jp 1997-2016. All Rights Reserved.